In recent years, equipment, which makes communication through an optical communication system using a plastic optical fiber cable, has been used in offices or somewhere else. Various sorts of connectors for connecting plastic optical fiber cables have been developed.
As one of methods for connecting plastic optical fiber cables, there has been known a method wherein one of plastic optical fiber cables, which is installed behind a wall or under a floor, has a leading end connected to a socket for a plastic optical fiber socket (hereinbelow, referred to as “optical socket”) through a connector in alignment fashion, and the optical socket is connected to the other plastic optical fiber cable through a connector in alignment fashion. For example, JP-A-9-127369, JP-A-1-189617 and JP-A-1-297604 disclose optical socket, which can be used in the method stated just above.
However, the optical socket disclosed in JP-A-9-127369 creates problems that it has no versatility since the attachment frame and the connecting unit are formed in a shape suited to a specific purpose, and that it cannot be directly installed. It also creates problems that the structure is complicated, that the number of parts is big, and that installation is difficult.
In addition, dust invasion need to be minimized since the invasion of dust degrades the transmission performance of optical sockets or optical connectors. Although the optical socket disclosed in JP-A-1-297604 has versatility since the optical socket is attachable to three modules in accordance with JIS standards, the optical socket creates a problem for lack of a dust proof construction since the optical socket has no member covering the connecting unit of the optical connector because of a decrease in the number of parts and simplification in the structure.
Further, since the plug is connected in a direction perpendicular to a wall surface to install, the optical socket creates a problem that the projection of the plug is great and the optical fiber cable is susceptible to be externally affected.
The optical socket disclosed in JP-A-1-189617 is provided in the form of one or two modules in accordance with the JIS standards and has the connector provided with a dustproof port cover. Although the optical socket has a structure wherein the port cover is manually opened and closed and is housed in the connector, the optical socket creates problems in operationality that the port cover is too small to handle, and that the opening and closing operation of the port cover and the connecting operation of a plug need to be separately carried out. In particular, poor operationality is creates a fatal problem since optical sockets are usually installed in a corner on a wall surface or the like.
Additionally, since the plug is connected in a direction perpendicular to a wall surface to install, the optical socket creates a problem that the projection of the plug is great and the optical fiber cable is susceptible to be externally affected.
Further, since the optical sockets disclosed in the prior art have a structure wherein a plug is merely inserted into the optical socket (optical connector), the optical sockets also create a problem that plastic optical fiber cables fail to be firmly abutted together because of loose connection. In particular, an optical socket (optical connector), which is formed for connection in a direction perpendicular to a wall surface, cannot maintain the high transmission performance since the connected portions are susceptible to become loose because of the weight of a plug with the passage of time.
It is an object of the present invention to solve these problems.
It is an object of the present invention to provide an assembly comprising an optical socket and a plug (hereinbelow, referred merely to as “assembly” in some cases), which is specifically described below:
1) An optical socket, which is attachable to three modules in accordance with the JIS standards, is provided so as to be applicable to existing wiring accessories and be versatile, expanding the application of the socket.
2) An optical socket and a plug, wherein the direction of connecting the plug and the receptacle is located so as to be parallel with a wall surface to install a plastic optical fiber cable, whereby the projection of the plug from the wall surface can be minimized, and the plastic optical fiber is hardly to be externally affected by furniture or the like for maintaining the transmission performance. And a socket, wherein light rays transmitted through a plastic optical fiber cable go out in a downward direction (in a direction toward a floor), and it is difficult for him or her to look into the optical socket, whereby safety can be ensured even if the plug is detached, and a person is not adversely affected.
3) An optical socket, wherein the tensile retainer has a cable guide formed so as to correspond to the recommended minimum radius of a plastic optical fiber cable, whereby the cable can be fixed to be prevented from being bent with a smaller radius than the recommended minimum radius of a plastic optical fiber cable during installation for maintaining the transmission performance.
4) An optical socket, wherein a port cover is provided at a slant angle conforming to the tapered shape of a receptacle connection port, whereby the gap between the port cover and a receptacle can be eliminated to prevent dust from entering.
5) An optical socket, wherein the port cover has a guiding surface provided at a lower position than a body top surface, whereby the guiding surface of the port cover can be made sure, and the port cover can be opened and closed easily and automatically.
6) An optical socket, wherein the guiding surface of the port cover has both lateral sides formed with guiding grooves so as to guide beam leading portions of the plug, whereby the opening and closing operation of the port cover can be made smooth and well-balanced, and a dust-proof construction can be provided.
7) An optical socket, wherein the body has a tapered shape defined by a surface, which is in contact with a circular arc having a radius corresponding to the recommended minimum radius of the plastic optical fiber cable, whereby the projection of the body from the wall surface can be reduced to improve appearance, and the number of required parts can be decreased to improve cost performance.
8) An optical socket, wherein the body has a plug inlet port provided with a supporting surface for supporting the plug after connection, whereby the plug is prevented from swinging in a direction perpendicular to the supporting surface after insertion of the plug, and the optical socket can provide stable support. And an optical socket and a plug, wherein even if the plug is externally affected, the plug can be supported by the supporting surface, making it difficult for the fiber cable to be externally affected directly.
9) An optical socket and a plug, wherein the supporting surface has a front edge chamfered in the direction of connecting the plug to the receptacle, whereby the plug can be inserted smoothly without a catch, and the projection of the body from a decorative plate can be reduced to improve appearance.
10) An optical socket, wherein the body has a rear side provided with a cable guide, which is formed with the recommended minimum radius of the plastic optical fiber cable, whereby the cable can be fixed to be prevented from be bent with a smaller radius than the recommended minimum radius during installation, maintaining transmission performance.
11) An optical socket, wherein the cable guide is provided at a position apart from the receptacle by a certain distance, whereby the plastic optical fiber inserted into the receptacle can be suppressed from swinging, avoiding external affection to the fiber.
12) An optical socket, wherein the body has a rear side provided with an engageable member so as to detachably mount the receptacle thereto, whereby the receptacle can be attached and detached easily, making installation easier.
13) An optical socket, wherein the tensile retainer has a ridge provided thereon to provide a fastening portion for sandwiching a plastic optical fiber cable, whereby the ridge as the fastening portion can prevent the plastic optical fiber cable from being drawn, which is assumed to be caused during installation, and the transmission performance can be maintained.
14) An optical socket, wherein the body and the tensile retainer have engageable members so as to detachably couple the body and the tensile retainer, whereby the tensile retainer can be easily detached from the body, making installation easier and expanding application range, in, e.g., the case wherein installation is carried out at a place where the gap behind the wall is narrow. And an optical socket, wherein the tensile retainer can be firmly held to stabilize the plastic optical fiber cable during installation and to maintain the transmission performance.
15) An optical socket, wherein the tensile retainer includes a rear plate having a narrower width than a wall-embedded box, the tensile retainer being housed in the wall-embedded box with the rear plate of the tensile retainer having the plastic optical fiber cable extending therearound, whereby the cable can be easily housed in the wall-embedded box during installation, making the installation easier.
16) An optical socket, wherein the receptacle, which is connected to a plastic optical fiber cable having an end aligned by cylindrical flexible parts (boots) having elasticity, is used, whereby workability is improved, and stress applied to the plastic optical fiber cable during bending can be dispersed to protect a plastic optical fiber.
17) an optical socket, wherein the receptacle, which includes a receptacle housing having an engagement space engageable with the plug, and a rear housing having a connector to be connected to a plastic optical fiber cable and formed so as to be reduced from the receptacle housing, is used, the receptacle can be firmly mounted to the body, and the receptacle can be firmly connected to the plug.
18) An optical socket and a plug, wherein the receptacle housing has gaps provided on both outer sides of a connection port (between lateral walls of the receptacle and the plug inlet port of the body) so as to engageable with the beams of the plug and leading portions of the beams, whereby the connection between the beams of the plug and the receptacle is made firm, preventing the plug from swinging in directions perpendicular to the connecting direction.
19) An optical socket, wherein the receptacle housing has a connection port formed in a tapered shape thereon, whereby the gap between the port cover and the receptacle can be eliminated, preventing dust from entering.
20) An optical socket, wherein the rear housing has a tapered guide and an engageable shoulder formed thereon, whereby it is possible to avoid mistaking the mounting direction of the receptacle.
21) An optical socket, wherein the rear housing has flanges, which are different from each other in terms of an increase in size, whereby it is possible to avoid mistaking the mounting direction of the receptacle.
22) An optical socket and a plug, wherein the receptacle is configured to house an engagement latch and beam leading portions of the plug in reduced portions of the rear housing, whereby the receptacle can be firmly fixed to the body, and the connection between the receptacle and the plug can be ensured.
23) A plug, wherein the beams have leading portions, each of which is longer than the engagement portion and has a projection tapered toward a leading edge, whereby the beams can be guided during connection to make the connection easier, to fasten the plastic optical fiber cable firmly, and to protect the engagement portion of the plug.
24) A plug, wherein the housing of the plug has a projected rib formed in a substantially semicircular shape on a substantially central portion on an outer surface thereof, whereby the rib can be brought into contact with the supporting surface of the body to prevent the plug from swinging in directions perpendicular to the supporting surface after insertion of the plug.
25) A plug, which includes an optical fiber cable fastener, which is formed in a U-character shape in section so as to have substantially the same width as a longer radius of the plastic optical fiber cable in section, and which has both side wall formed with slits to sandwich a tension member of the plastic optical fiber cable therein; and a fiber cable fastener housing groove to house the optical fiber cable fastener therein, whereby even if the plug is externally affected, the fiber is hardly to be directly and externally affected since the engagement portion can be protected.
26) a plug, wherein the optical fiber cable fastener housing groove has a rear portion provided with a cable holding projection to sandwich the plastic optical fiber cable therebetween, whereby a plastic optical fiber cable can be held more firmly.
27) A plug, wherein the engagement space of the receptacle housing includes engageable grooves formed in asymmetric fashion so as to be engageable with engageable members of the plug; the engagement portion of the plug includes an engageable cover, which has ridges formed on upper and lower surfaces on and along one of lateral sides in a longitudinal direction thereof; and the housing of the plug has engageable cover fastening grooves engraved on a leading portion in a substantially central portion, the engageable cover fastening grooves extending along one of lateral sides so as to be engageable with the ridges on the engageable cover, whereby it is possible to avoid mistaking the connecting direction (the connecting sides).